HSG80 ACS Solution Software Version 8.7 for Compaq OpenVMS Installation and Configuration Guide

Planning Storage Configurations
2–3HSG80 ACS Solution Software Version 8.7 for Compaq OpenVMS Installation and
Configuration Guide
2–3
— Use the Command Line Interpreter (CLI) commands. This method allows you
flexibility in defining and naming your storage containers. See the
StorageWorks HSG80 Array Controller ACS Version 8.7 CLI Reference
Guide.
Determining Storage Requirements
It is important to determine your storage requirements. Here are a few of the questions
you should ask yourself regarding the subsystem usage:
• What applications or user groups will access the subsystem? How much capacity
do they need?
• What are the I/O requirements? If an application is data transfer-intensive, what is
the required transfer rate? If it is I/O request-intensive, what is the required
response time? What is the read/write ratio for a typical request?
• Are most I/O requests directed to a small percentage of the disk drives? Do you
want to keep it that way or balance the I/O load?
• Do you store mission-critical data? Is availability the highest priority or would
standard backup procedures suffice?
Configuration Rules for the Controller
The following list defines maximum configuration rules for the controller:
• 128 visible LUNs/200 assignable unit numbers
— In SCSI-3 mode, if the CCL is enabled, the result is 126 visible LUNs and two
CCLs.
• 1.024 TB storageset size
• 96 host connections
• 84 physical devices
• 20 RAID 3/5 storagesets
• 30 RAID 3/5 and RAID 1 storagesets (see note)
• 45 RAID 3/5, RAID 1, and RAID 0 storagesets (see note)
NOTE: For the previous two storageset configurations, this is a combined maximum, limited to
no more than 20 RAID 3/5 storagesets in the individual combination.